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Police forces across the UK effectively campaigned to deploy a facial recognition system acknowledged as discriminatory against females, young people, and individuals from ethnic minority groups, after complaining that a less biased version produced a reduced number of potential suspects.

How the System Works

UK forces utilize the national police database to carry out retrospective facial recognition searches. This procedure involves matching a reference photograph of a suspect against a repository of more than 19 million mugshots to find possible hits.

Admitted Bias

The UK interior ministry admitted last week that the technology was biased. This admission came after a review by the National Physical Laboratory (NPL) found it misidentified Black and Asian people and females at much greater frequency than white men. The Home Office stated it “had acted on the findings”.

“It prompts the question of whether this technology only becomes useful if users tolerate discrimination in ethnicity and gender. Operational ease is a poor argument for disregarding basic freedoms.”

Long-Standing Problem

Official papers reveal that this bias has been recognized for over twelve months. Furthermore, police forces lobbied to reverse an earlier ruling that was designed to mitigate the problem.

Police bosses were notified of the system's bias in late 2024. The government-ordered NPL review found the system was more likely to produce false positives for images depicting females, Black people, and those aged 40 and under.

A Reversed Decision

In reaction, the national police leadership body mandated that the confidence threshold required for possible hits be raised to a level where the bias was significantly reduced.

However, this decision was reversed the following month following complaints from police that the modified technology was producing a lower number of “investigative leads”. Internal records show the stricter setting reduced the proportion of queries resulting in possible identifications from over half to a just 14%.

Profound Inequalities

Although the authorities refused to say what threshold is currently used, the recent NPL study discovered the system could produce incorrect matches for women of Black heritage nearly a hundred times more frequently than for white women at certain settings.

The Home Office stated on these results: “Our evaluation identified that in a specific scenarios the software is more likely to wrongly flag some demographic groups in its search results.”

Operational Effectiveness vs. Bias

Describing the impact of the brief increase to the system's confidence threshold, the NPCC documents state: “This adjustment significantly reduces the effect of discrimination across protected characteristics of race, age and sex but had a substantially detrimental effect on police efficiency”. The documents add that forces complained that “a once effective tactic returned results of limited benefit”.

Broader Rollout Plans

Meanwhile, the government has opened a two-and-a-half-month consultation on its plans to widen the use of biometric scanning systems. Policing minister the relevant minister has labeled the technology as the “biggest breakthrough since genetic fingerprinting”.

Expert and Oversight Concerns

The chair of a police oversight board, chair of the independent scrutiny and oversight board for the police race action plan, said: “We observed scant consideration in equality strategy sessions of the facial recognition rollout despite obvious cross-over with the plan’s concerns.

“These revelations demonstrate yet again that the anti-racism commitments the police has made through the equality initiative are failing to be integrated into wider practice. Our reports have warned that innovative tools are being implemented in a landscape where racial disparities, weak scrutiny and faulty information gathering continue to exist.

“All deployment of facial recognition must adhere to rigorous official guidelines, be independently scrutinised, and demonstrate it reduces rather than compounds racial disparity.”

Official Statement

A government representative stated: “We takes the findings of the study seriously and we have already taken action. A updated software has been externally evaluated and procured, which has demonstrated no measurable discrimination. It will be trialled early next year and will be subject to further assessment.

“The foremost aim is protecting the public. This gamechanging technology will assist police to apprehend and prosecute offenders. There is human involvement in each stage of the procedure and no arrest or charge would be pursued without specialist personnel meticulously examining the results.”